drivers/touchpad_st.c: wait full initialize by re-calling deferred
drivers/touchpad_st.c: wait full initialize by re-calling deferred

Full panel initialization can take about 1.6 seconds.  If this is
called by hook_call_deferred, it will block other HOOKS.  Replace the
'while loop + sleep' by re-calling deferred every 100ms.

BRANCH=whiskers
BUG=b:109714732
TEST=sudo ./extra/usb_updater/usb_updater2 -d 18d1:5030 --tp_update <fw>
TEST=sudo extra/usb_updater/usb_updater2 -d 18d1:5030 --tp_debug=01
TEST=(EC console) touchpad_st calibrate
Signed-off-by: Wei-Han Chen <5413a119f383c3f4549c3ef659403f393bf06e9d@chromium.org>

Change-Id: I665169524a06a7c359303a4a3dceced4a141f9ae
Reviewed-on: https://chromium-review.googlesource.com/1086895
Commit-Ready: ChromeOS CL Exonerator Bot <fa429e5907f00867f797423aea74327bb02c91b6@appspot.gserviceaccount.com>
Tested-by: Wei-Han Chen <5413a119f383c3f4549c3ef659403f393bf06e9d@chromium.org>
Reviewed-by: Nicolas Boichat <f3daba1cdc403799935674d3cd4b0e5bd1804232@chromium.org>
Reviewed-by: Vincent Palatin <70a9964ec8fd10b0b08fcc8623c2add25ddf99ac@chromium.org>

coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec